1. Field of the Invention
This invention relates to a vehicle assistance control apparatus.
2. Description of Related Art
A vehicle assistance control apparatus is available, in which sudden movement of a host vehicle is prohibited on the basis of an obstacle present in the periphery of the vehicle (see, for example, Japanese Patent Application Publication No. 5-124453 (JP 5-124453 A) and Japanese Patent Application Publication No. 2013-133770 (JP 2013-133770 A)). The apparatus described in JP 5-124453 A prohibits sudden movement of the host vehicle by restricting the drive power of the host vehicle in such a manner that the engine number of revolutions does not increase beyond a prescribed level, when a detected obstacle is situated within a prescribed distance from the host vehicle. Consequently, according to this apparatus, it is possible to diminish shocks with obstacles due to sudden starting off of the host vehicle.
Furthermore, the apparatus described in JP 2013-133770 A prohibits sudden movement by restricting the drive power of the host vehicle when an increase in the acceleration depression amount is detected due to an accelerator operation, in cases where a detected obstacle is situated within a prescribed distance from the host vehicle, whereas the abovementioned prohibition of sudden movement (in other words, restriction of the drive power) is cancelled in cases where the host vehicle speed is zero and a state of the accelerator depression amount being equal to or greater than a prescribed amount due to an accelerator operation has continued for a prescribed period of time or longer. Consequently, according to this apparatus, it is possible to generate a large torque, as normal, according to the driver's wishes, when it is necessary, for instance, to drive the host vehicle over an obstacle such as a step, or the like, while preventing collision with an obstacle due to sudden starting off the host vehicle.
However, in the apparatus described in JP 5-124453 A, the drive power is always restricted when an obstacle is situated within a prescribed distance. Consequently, for instance, when snow or dirt becomes attached to the sensor which detects obstacles, then there is a possibility of the sensor erroneously recognizing that an obstacle is situated within a prescribed distance, and hence of not being able to ensure normal accelerating performance in accordance with the accelerator operation.
Furthermore, in the apparatus described in JP 2013-133770 A, even after the drive power of the host vehicle has been restricted, the restriction of drive power is cancelled provided that prescribed conditions are established, and therefore it is possible to ensure normal acceleration performance in accordance with the driver's wishes. However, since the fact that an accelerator operation has continued for a prescribed time or longer is specified as a condition for cancelling the restriction of drive power, then it is not possible to cancel the restriction of drive power unless the accelerator operation has continued for a prescribed time or longer. For example, when the host vehicle is being driven over an obstacle, such as a step, or the like, there is a possibility that the restriction of drive power will not be cancelled if the driver interrupts the accelerator operation midway through.